<!doctype html>
<html lang="en">
 <head>
  <meta charset="UTF-8">
  <meta name="Generator" content="EditPlus®">
  <meta name="Author" content="">
  <meta name="Keywords" content="">
  <meta name="Description" content="">
  <title>Document</title>
  <style>
     #div{
	    width:200px;
		height:50px;
		background-color:yellow;
		font-size:15px;
		text-align:center;
		line-height:50px;
	 }
  </style>
 </head>
 <body>
    <div id="div" onmouseover="over()" onmouseout="out()">请移入鼠标<div>
 </body>
  <script>
      var div = document.getElementById("div");
	  function over(){
	     div.innerText = "你已经移入了鼠标";
	  }
	  function out(){
	    div.innerText = "请移入鼠标";
	  }
  </script>
</html>
